package com.yupi.springbootinit.utils;

import cn.hutool.core.collection.CollUtil;
import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.support.ExcelTypeEnum;
import com.qcloud.cos.utils.StringUtils;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.ObjectUtils;
import org.springframework.util.ResourceUtils;
import org.springframework.web.multipart.MultipartFile;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

/**
 * Excel工具类
 *
 */
@Slf4j
public class ExcelUtils {
    public static  String excelToCsv(MultipartFile multipartFile)  {
        File file = null;
      /*  try {
            file = ResourceUtils.getFile("classpath:网站数据.xlsx");
        } catch (FileNotFoundException e) {
            throw new RuntimeException(e);
        }*/


        List<Map<Integer, String>> list = null;
        try {
            list = EasyExcel.read(multipartFile.getInputStream())
                    .excelType(ExcelTypeEnum.XLSX)
                    .sheet()
                    .headRowNumber(0)
                    .doReadSync();
        } catch (IOException e) {
            log.error("表格处理错误", e);
        }

        if (CollUtil.isEmpty(list)){
            return "";
        }
        //转换为csv
        StringBuilder stringBuilder = new StringBuilder();
        //读取表头
        LinkedHashMap<Integer, String> headMap = (LinkedHashMap)list.get(0);
        List<String> headList = headMap.values().stream().filter(header -> header != null).collect(Collectors.toList());
        stringBuilder.append(String.join(",", headList)).append("\n");

        //读取数据
        for (int i = 1; i < list.size(); i++){
            LinkedHashMap<Integer, String> dataMap = (LinkedHashMap)list.get(i);
            List<String> dataList = dataMap.values().stream().filter(data -> data != null).collect(Collectors.toList());
            stringBuilder.append(String.join(",", dataList)).append("\n");
        }
        return stringBuilder.toString();
    }

    public static void main(String[] args) {
        excelToCsv(null);
    }




}
